High Programmed Death-ligand 1 Research Articles

PD-L1+ Lymphocytes Are Associated with CD4+, Foxp3+CD4+, IL17+CD4+ T Cells and Subtypes of Macrophages in Resected Early-Stage Non-Small Cell Lung Cancer.

The non-canonical PD-L1 pathway revealed that programmed-death ligand 1 (PD-L1) expression in immune cells also plays a crucial role in immune response. Moreover, immune cell distribution in a tumour microenvironment (TME) is pivotal for tumour genesis. However, the results remain controversial and further research is needed. Distribution of PD-L1-positive (PD-L1+) tumour-infiltrating lymphocytes in the context of TME was assessed in 72 archival I-III stage surgically resected NSCLC tumour specimens. Predominant PD-L1+ lymphocyte distribution in the tumour stroma, compared to islets, was found (p = 0.01). Higher PD-L1+ lymphocyte infiltration was detected in smokers due to their predominance in the stroma. High PD-L1+ lymphocyte infiltration in tumour stroma was more common in tumours with higher CD4+ T cell infiltration in islets and stroma, Foxp3+CD4+ T cell infiltration in islets and lover M1 macrophage infiltration in the stroma (p = 0.034, p = 0.034, p = 0.005 and p = 0.034 respectively). Meanwhile, high PD-L1+ lymphocyte infiltration in islets was predominantly found in tumours with high levels of IL-17A+CD4+ T cells in islets and Foxp3+CD4+ T cells in islets and stroma (p = 0.032, p = 0.009 and p = 0.034, respectively). Significant correlations between PD-L1+ lymphocytes and tumour-infiltrating CD4+, Foxp3+CD4+, IL-17A+CD4+ T cells and M2 macrophages were found. An analysis of the tumour-immune phenotype revealed a significant association between PD-L1 expression and IL17+CD4+ and Foxp3+CD4+ immune phenotypes. PD-L1+ lymphocytes are associated with the distribution of CD4+, Foxp3+CD4+, IL17A+CD4+ T cells, M1 and M2 macrophages in TME of resected NSCLC.

Brief Report: Not Created Equal: Survival Differences by KRAS Mutation Subtype in NSCLC Treated With Immunotherapy

IntroductionThe predictive and prognostic implications of different KRAS mutation (KRASm) subtypes in metastatic NSCLC have not been clearly defined. We used a nationwide observational database to investigate whether KRASm subtypes differ in their association with survival in metastatic NSCLC treated with immune checkpoint inhibitor (ICI)-based therapy, across programmed death-ligand 1 (PD-L1) levels. MethodsPatients with advanced nonsquamous NSCLC who initiated first-line ICI-based therapy from 2016 to 2021 and had known PD-L1 expression and comprehensive genomic profiling including KRAS, STK11, KEAP1, and TP53 were included. Within PD-L1 expression subgroups (<1%, 1%–49%, ≥50%), Cox multivariable regression was used to evaluate the association between KRASm subtypes (G12C, G12V, G12D, other KRASm) and overall survival, estimated using Kaplan-Meier methodology. ResultsAmong the 1539 patients, 819 patients were KRAS wild type (KRASwt) and 720 were KRASm (296 KRAS G12C, 143 KRAS G12V, 97 KRAS G12D, 184 other KRASm). In the 50% or higher PD-L1 subgroup, patients with KRAS G12V had worse survival (median overall survival [mOS] = 8.2 mo) compared with KRASwt (mOS = 13.3 mo) and other KRAS subgroups (mOS ranging from 13.4 to 19.9 mo). On adjusted Cox multivariable regression in the 50% or higher PD-L1 subgroup, the hazard ratio for death for KRAS G12V ranged from 1.53 to 1.78 compared with KRASwt and other KRASm subtypes (all p < 0.05). ConclusionsAlthough patients with 50% or higher PD-L1 with KRAS G12C, G12D, and other subtypes exhibited similar survival to KRASwt, KRAS G12V was associated with significantly worse survival than KRASwt and other KRASm subtypes. All KRASm should not be regarded as uniform predictors of ICI responsiveness, even with high PD-L1 expression; KRAS G12V tumors may have worse outcomes with ICI-based therapy and benefit from treatment intensification.

PD-L1 as a Biomarker for the Efficacy of Durvalumab in Stage III EGFR Mutant NSCLC.

Durvalumab consolidation is less effective in patients with epidermal growth factor receptor mutant (EGFR M+) NSCLC. Studies of durvalumab on EGFR M+ NSCLC as an expression of programmed death-ligand 1 (PD-L1) expression are limited. The purpose of this study was to determine the effect of durvalumab on PD-L1 expression in EGFR M+ patients. This study included 249 unresectable stage III NSCLC patients treated with durvalumab. The primary outcome was progression-free survival (PFS). Cox multivariate analysis was performed based on EGFR and PD-L1 statuses: EGFR M-, PD-L1 ≥50% (cohort A); EGFR M-, PD-L1 <50% (cohort B); EGFR M+, PD-L1 ≥50% (cohort C); and EGFR M+, PD-L1 <50% (cohort D). Overall, 31 of 249 (12.4%) and 218 of the 249 (87.6%) patients had EGFR M+ and EGFR M- NSCLC, respectively. Median PFSs and OSs did not differ (PFS: 16.6 vs. 18.7 months, p=0.591; OS: 37.4 vs. 35.7 months, p=0.271). Median PFS of cohort A did not significantly differ from the median PFSs of cohorts B and C, but it was significantly longer than the median PFS of cohort D (23.7 vs. 15.2 months, p=0.045). Cox multivariate analysis revealed that cohort D exhibited a worse PFS (adjusted hazard ratio=2.27, 95% confidence interval=1.11-4.66, p=0.025) compared with cohort A. Median OSs were not different between the four cohorts. Durvalumab consolidation provided similar benefit in EGFR M+ patients with PD-L1 ≥50% compared with EGFR M- patients. A therapeutic role of durvalumab in patients with EGFR M+, high PD-L1 unresectable stage III NSCLC should be considered.

The efficacy and safety of neoadjuvant immunochemotherapy in resectable stage I-III non-small cell lung cancer: a systematic review and network meta-analysis.

Neoadjuvant immunochemotherapy (NICT) is a new treatment method for resectable non-small-cell lung cancer (NSCLC). Network meta-analysis assessed efficacy, safety, and optimal treatment. We searched for randomized controlled trials (RCTs) comparing NICT with neoadjuvant chemotherapy (NCT) in PubMed, Embase, Web of Science, Cochrane Library, and international conferences. Outcomes were surgical resection rate, pathological complete response(pCR),event-free survival (EFS), and Grade 3-5 treatment-related adverse events (TRAEs). RCTs of 3,387 patients, six treatment combinations, and two modalities were included. Meta-analysis showed that NICT yielded higher pCR and EFS rates than NCT. The toripalimab-chemotherapy combination had the highest surgical resection rate (OR = 1.68, 95% CI: 1.05-2.73), pCR (OR = 38.84, 95% CI: 11.05-268.19) and EFS (HR = 0.40, 95% CI: 0.28-0.58).This regimen worked well for patients with low programmed death-ligand 1 (PD-L1) expression or squamous cell pathology. For high PD-L1 expression and patients with NSCLC, neoadjuvant nivolumab with chemotherapy had the most efficacy. The incidence of treatment-related adverse events increased with longer treatment cycles, with perioperative nivolumab combined with chemotherapy showing the worst safety profile (RR = 1.32, 95% CI: 1.00-1.76), while neoadjuvant nivolumab combined with chemotherapy alone had the best safety profile (RR = 0.91, 95% CI: 0.68-1.21). Indirect comparison showed no survival benefit for neoadjuvant-adjuvant immunotherapy (HR = 0.93, 95% CI: 0.65-1.35). In the indirect comparison between the two immune checkpoint inhibitors(ICIs), although there was no significant difference in EFS (HR = 0.81, 95% CI: 0.61-1.08), PD-1 inhibitors may still be the most effective treatment option. NICT effectively and safely treats resectable NSCLC. The optimal treatment combination is typically toripalimab and chemotherapy. Treatment based on PD-L1 expression and pathological type is recommended.

Study on the mechanism of liver cancer immune escape mediated by MINDY1 through regulation of PD-L1 ubiquitination level.

The novel deubiquitinase enzyme, motif interacting with ubiquitin-containing novel DUB family-1 (MINDY1), is highly expressed in liver cancer tissues and plays a crucial role in maintaining the stemness of liver cancer cells. Programmed death ligand-1 (PD-L1) is an immunosuppressive molecule overexpressed by tumour cells. The potential role of MINDY1 in inhibiting the stemness of liver cancer cells by deubiquitinating PD-L1 has not yet been reported. To investigate the mechanism by which MINDY1 mediates immune escape in liver cancer through the regulation of PD-L1 ubiquitination, we examined the expression levels of MINDY1 and PD-L1 in liver cancer and adjacent tissues from 50 hepatocellular carcinoma (HCC) patients using protein imprinting and immunohistochemistry. We analyzed the relationship between the expression levels of MINDY1 and PD-L1 in liver cancer tissues and their correlation with the 5-year tumor-free survival rates of patients. Subsequently, MINDY1 expression was knocked down in Huh7 cells using small interfering RNA (siRNA) interference or upregulated through transfection with a MINDY1 overexpression plasmid. The effects of MINDY1 knockdown or overexpression on the proliferation, apoptosis, migration, and invasion of HCC cells, as well as the regulation of PD-L1 binding and ubiquitination, were assessed. The 5-year tumor-free survival rates were significantly lower in both the high MINDY1 expression group and the high PD-L1 expression group (χ2 = 4.919 and 13.158, respectively).A significant difference in survival was observed between the high and low MINDY1 expression groups (χ2= 27.415). MINDY1 was found to directly interact with PD-L1, with MINDY1 gene knockdown promoting PD-L1 ubiquitination and MINDY1 overexpression inhibiting PD-L1 ubiquitination. All comparisons yielded statistically significant results (P < 0.05). In conclusion, MINDY1 inhibits the malignant progression of liver cancer by inhibiting PD-L1 ubiquitination and mediating immune escape.

Depth of response and treatment outcomes of immune checkpoint inhibitor-based therapy in patients with advanced non-small cell lung cancer and high PD-L1 expression: An exploratory analysis of retrospective multicenter cohort.

The association between depth of response (DpR) and treatment outcomes has been documented across various types of cancer. Immune checkpoint inhibitor (ICI)-based treatment is globally used as first-line treatment for non-small cell lung cancer (NSCLC) with programmed death-ligand 1 (PD-L1) expression ≥ 50%. However, in this population, the significance of DpR is not elucidated. Patients with advanced NSCLC and PD-L1 expression ≥ 50% who received ICI-monotherapy or ICI plus chemotherapy were retrospectively enrolled into this study. Treatment responses were grouped into DpR 'quartiles' by percentage of maximal tumor reduction (Q1 = 1-25%, Q2 = 26-50%, Q3 = 51-75%, and Q4 = ≥ 76%), and no tumor reduction (NTR). The association between DpR and survival rates were determined using hazard ratios (HR) generated by the Cox proportional hazards model. The Kaplan-Meier method was used to determine survival outcomes. A total of 349 patients were included, of which 214 and 135 patients received pembrolizumab monotherapy and ICI plus chemotherapy, respectively, as first-line treatments. The majority of the patients were male. All DpR quartiles, especially Q4, showed an association with progression-free survival (PFS)/overall survival (OS). In the Q4 cohort, patients who received pembrolizumab had a longer PFS than those who received ICI plus chemotherapy. High DpR was associated with longer PFS and OS, with a more pronounced effect observed with pembrolizumab monotherapy than with ICI plus chemotherapy.

Three-dimensional iodine mapping quantified by dual-energy CT for predicting programmed death-ligand 1 expression in invasive pulmonary adenocarcinoma

We examined the association between texture features using three-dimensional (3D) io-dine density histogram on delayed phase of dual-energy CT (DECT) and expression of programmed death-ligand 1 (PD-L1) using immunostaining methods in non-small cell lung cancer. Consecutive 37 patients were scanned by DECT. Unenhanced and enhanced (3 min delay) images were obtained. 3D texture analysis was performed for each nodule to obtain 7 features (max, min, median, mean, standard deviation, skewness, and kurtosis) from iodine density mapping and extracellular volume (ECV). A pathologist evaluated a tumor proportion score (TPS, %) using PD-L1 immunostaining: PD-L1 high (TPS ≥ 50%) and low or negative expression (TPS < 50%). Associations between PD-L1 expression and each 8 parameter were evaluated using logistic regression analysis. The multivariate logistic regression analysis revealed that skewness and ECV were independent indicators associated with high PD-L1 expression (skewness: odds ratio [OR] 7.1 [95% CI 1.1, 45.6], p = 0.039; ECV: OR 6.6 [95% CI 1.1, 38.4], p = 0.037). In the receiver-operating characteristic analysis, the area under the curve of the combination of skewness and ECV was 0.83 (95% CI 0.67, 0.93) with sensitivity of 64% and specificity of 96%. Skewness from 3D iodine density histogram and ECV on dual energy CT were significant factors for predicting PD-L1 expression.

PD-L1 expression and its correlation with tumor biomarkers in Chinese urothelial bladder cancer

Data on prevalence of programmed death ligand-1 (PD-L1) expression and its correlation with tumor biomarkers in Chinese patients with muscle-invasive urothelial bladder cancer (MIUBC) are scarce. We investigated the prevalence of PD-L1 expression, PD-L1 expression in tumor cells (TC) and immune cells (IC), and its correlation with tumor biomarkers (CD8+ T cells and tumor mutation burden [TMB]) in Chinese patients with newly diagnosed MIUBC (NCT03433924). Of 248 patients enrolled, 229 with PD-L1 data available were analysed. High PD-L1 expression (≥ 25% of TC or IC with PD-L1 expression) was observed in 120 (52.4%) patients. 59 cases showed positive staining in ≥ 25% of TC, and 82 cases had positive staining in ≥ 25% of IC. High expression of CD8+ T cell and TMB (> 10 mutations/megabase) was observed in 44.5% and 54.1% patients, respectively. A positive correlation was observed between percentage of TC with membrane PD-L1 positivity and CD8+ T cells (0.34; P < 0.001) and between IC with membrane PD-L1 positivity and CD8+ T cells (0.44; P < 0.001). There is high prevalence of PD-L1 expression in Chinese patients with MIUBC, suggesting that a sizable subset of patients could benefit from immunotherapy. The correlation of PD-L1 expression with tumor biomarkers provide clues for mechanisms underlying the effects of biomarkers for predicting efficacy.

Unraveling the influence of TTF-1 expression on immunotherapy outcomes in PD-L1-high non-squamous NSCLC: a retrospective multicenter study.

Several studies explored the association between thyroid transcription factor-1 (TTF-1) and the therapeutic efficacy of immunotherapy. However, the effect of TTF-1 on the therapeutic efficacy of programmed death-1 (PD-1) inhibitor/chemoimmunotherapy in patients with non-squamous non-small cell lung cancer (non-Sq NSCLC) with a programmed death-ligand 1 (PD-L1) tumor proportion score of 50% or more who are highly susceptible to immunotherapy remains unresolved. Therefore, we evaluated whether TTF-1 has a clinical impact on this population. Patients with non-Sq NSCLC and high PD-L1 expression who received PD-1 inhibitor monotherapy or chemoimmunotherapy between May 2017 and December 2020 were retrospectively enrolled. Treatment efficacy was compared after adjusting for baseline differences using propensity score matching. Among the 446 patients with NSCLC with high PD-L1 expression, 266 patients with non-Sq NSCLC were analyzed. No significant differences in therapeutic efficacy were observed between the TTF-1-positive and -negative groups in the overall and propensity score-matched populations. Of chemoimmunotherapy, pemetrexed containing regimen significantly prolonged progression-free survival compared to chemoimmunotherapy without pemetrexed, regardless of TTF-1 expression (TTF1 positive; HR: 0.46 (95% Confidence interval: 0.26-0.81), p<0.01, TTF-1 negative; HR: 0.29 (95% Confidence interval: 0.09-0.93), p=0.02). TTF-1 expression did not affect the efficacy of PD-1 inhibitor monotherapy or chemoimmunotherapy in patients with non-Sq NSCLC with high PD-L1 expression. In this population, pemetrexed-containing chemoimmunotherapy demonstrated superior anti-tumor efficacy, irrespective of TTF-1 expression.

Real-world first-line treatment with pembrolizumab for non-small cell lung carcinoma with high PD-L1 expression: Updated analysis.

Selecting pembrolizumab monotherapy (MONO) or pembrolizumab plus platinum-based chemotherapy (COMB) for patients with nonsmall cell lung cancer (NSCLC) and high programmed death-ligand 1 (PD-L1) expression is an important issue in clinical practice. We previously conducted a retrospective multicenter observational study of patients with NSCLC and high PD-L1 expression who received MONO or COMB as a first-line treatment. Here, we report updated data and evaluate the long-term outcomes. We performed a retrospective multicenter study of 298 patients with NSCLC and high PD-L1 expression who received MONO or COMB as first-line treatment between December 2018 and January 2020. We reviewed the medical records and assessed the clinical efficacy and toxicity using a prolonged data cutoff. In total, 164 (median age: 74 years) and 134 (median age: 68 years) patients received MONO and COMB, respectively; patients who received COMB were younger and had better performance statuses (0-1). At the prolonged data cutoff, the median follow-up was 20.2 (range: 0.1-41.4) months. The median progression-free survivals were 7.5 and 13.1 months, and overall survivals (OSs) were 17.2 and 33.7 months for MONO and COMB, respectively. Treatment discontinuation rates were 21.9% and 20.1% for the MONO and COMB, respectively. With prolonged follow-up, although COMB demonstrated an OS benefit and higher objective response rate than MONO, in the propensity score matching analysis COMB didn't demonstrate a significant benefit compared to the MONO. COMB may be effective as a first-line treatment for NSCLC with high PD-L1 expression in a selected subset of patients.

Circulating receptor activator of nuclear factor kappa-B ligand (RANKL) levels predict response to immune checkpoint inhibitors in advanced non-small cell lung cancer (NSCLC)

BackgroundReceptor activator of nuclear factor kappa-B ligand (RANKL) can directly promote tumor growth and indirectly support tumor immune evasion by altering the tumor microenvironment and immune cell responses. This study...

Neoadjuvant Nivolumab Plus Chemotherapy Followed By Response-Adaptive Therapy for HPV+ Oropharyngeal Cancer

Immune checkpoint inhibitors improve survival in recurrent and/or metastatic head and neck cancer, yet their role in curative human papillomavirus-positive oropharyngeal cancer (HPV+ OPC) remains undefined. Neoadjuvant nivolumab and chemotherapy followed by response-adaptive treatment in HPV+ OPC may increase efficacy while reducing toxicity. To determine the deep response rate and tolerability of the addition of neoadjuvant nivolumab to chemotherapy followed by response-adapted locoregional therapy (LRT) in patients with HPV+ OPC. This phase 2 nonrandomized controlled trial conducted at a single academic center enrolled 77 patients with locoregionally advanced HPV+ OPC from 2017 to 2020. Data analyses were performed from February 10, 2021, to January 9, 2023. Addition of nivolumab to neoadjuvant nab-paclitaxel and carboplatin (studied in the first OPTIMA trial) followed by response-adapted LRT in patients with HPV+ OPC stages III to IV. Primary outcome was deep response rate to neoadjuvant nivolumab plus chemotherapy, defined as the proportion of tumors with 50% or greater shrinkage per the Response Evaluation Criteria in Solid Tumors 1.1. Secondary outcomes were progression-free survival (PFS) and overall survival (OS). Swallowing function, quality of life, and tissue- and blood-based biomarkers, including programmed death-ligand 1 (PD-L1) expression and circulating tumor HPV-DNA (ctHPV-DNA), were also evaluated. The 73 eligible patients (median [range] age, 61 [37-82] years; 6 [8.2%] female; 67 [91.8%] male) started neoadjuvant nivolumab and chemotherapy. Deep responses were observed in 51 patients (70.8%; 95% CI, 0.59-0.81). Subsequent risk- and response-adaptive therapy was assigned as follows: group A, single-modality radiotherapy alone or transoral robotic surgery (28 patients); group B, intermediate-dose chemoradiotherapy of 45 to 50 Gray (34 patients); and group C, regular-dose chemoradiotherapy of 70 to 75 Gray (10 patients). Two-year PFS and OS were 90.0% (95% CI, 0.80-0.95) and 91.4% (95% CI, 0.82-0.96), respectively. By response-adapted group, 2-year PFS and OS for group A were 96.4% and 96.4%, and group B, 88.0% and 91.0%, respectively. Lower enteral feeding rates and changes in weight, as well as improved swallowing, were observed among patients who received response-adapted LRT. Pathologic complete response rate among patients who underwent transoral robotic surgery was 67.0%. PD-L1 expression was nonsignificantly higher for deeper responses and improved PFS, and ctHPV-DNA clearance was significantly associated with improved PFS. This phase 2 nonrandomized controlled trial found that neoadjuvant nivolumab and chemotherapy followed by response-adapted LRT is feasible and has favorable tolerability, excellent OS, and improved functional outcomes in HPV+ OPC, including among patients with high-risk disease. Moreover, addition of nivolumab may benefit high PD-L1 expressors, and sensitive dynamic biomarkers (eg, ctHPV-DNA) are useful for patient selection. ClinicalTrials.gov Identifier: NCT03107182.

Impact of PD-L1 Expression on the Overall Survival of Caucasian Patients with Advanced EGFR-Mutant NSCLC Treated with Frontline Osimertinib.

The treatment of advanced non-small cell lung cancer (NSCLC) harboring an oncogenic epidermal growth factor receptor mutation (EGFRm) is currently based on osimertinib, a third-generation tyrosine kinase inhibitor (TKI). High Programmed death ligand 1 (PD-L1) expression ≥ 50% demonstrated to be a negative prognostic factor, mostly among Asian populations treated with 1st/2nd generation TKI. We investigated the impact of PD-L1 expression on the progression free survival (PFS) and overall survival (OS) within a cohort of patients receiving osimertinib as first-line treatment. Our bi-centre French retrospective study included all newly diagnosed patients with an advanced EGFRm (common and uncommon) NSCLC, between May 2018 and November 2022, treated with osimertinib. The primary endpoint was OS according to tumor proportion score PD-L1 expression (low/intermediate < 50% vs high ≥ 50%). Survival analyses were performed using Kaplan-Meier method and Cox model for adjusted multivariate analysis. Of 96 patients, median age was 71 (IQR 62-76), 70 were women (72.9%), 81 had a performance status (PS) 0-1 (84.3%). Median follow-up was 22.6 months (95% CI 20.5-24.7). Twenty patients (20.8%) had high PD-L1 expression ≥ 50%. No significant differences in baseline characteristics were observed based on PD-L1 status. Patients with PD-L1 ≥ 50% had significant shorter PFS and OS than those with PD-L1 < 50%, respectively 9.3 vs 17.5 months (p = 0.044 months) and 14.3 vs 26.0 months (p = 0.025). Multivariable adjustment for baseline characteristics found that PS ≥ 2 (HR 2.79, 95% CI 1.12-6.93, p = 0.027), PD-L1 ≥ 50% (HR 2.61, 95% CI 1.31 to 5.22, p = 0.007) and uncommon EGFR mutation (HR 4.59, 95% CI 1.95-10.80, p = <0.001) were associated with a shorter OS. Brain metastases at diagnosis and age ≥ 65 were not, respectively HR 1.66 (95% CI 0.90-3.06, p = 0.11) and HR 0.95 (95% CI 0.50-1.80, p=0.9). Our study found that PD-L1 expression ≥ 50% was associated with a shorter OS in EGFRm NSCLC patients treated with first line osimertinib. Further research is warranted to understand the underlying molecular and cellular mechanisms of this correlation.

HB-200 arenavirus-based immunotherapy plus pembrolizumab as first-line treatment of patients with recurrent/metastatic HPV16-positive head and neck cancer: Updated results.

6005 Background: Treatment options are limited for patients with recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) with no approved treatment specifically targeting human papillomavirus (HPV) 16-positive tumors. In the first-line (1L) R/M setting, only a minority of patients (~20%) respond to pembrolizumab monotherapy, including those with high programmed death ligand 1 (PD-L1) expression in the tumor. HB-200 comprises an alternating sequence of two replicating attenuated arenavirus vectors derived from LCMV (HB-201) and Pichinde virus (HB-202), respectively. HB-200 vectors express a non-oncogenic HPV16 E7E6 fusion protein and induce E6 and E7-specific CD8 T-cell responses. Previously, we reported promising preliminary clinical activity of HB-200 in combination with pembrolizumab as 1L treatment for patients with HPV16+ PD-L1+ R/M HNSCC. Here, we report updated results with a focus on PD-L1 status. Methods: In this non-randomized Phase 2 part of the study, participants with HPV16+ PD-L1 combined positive score (CPS) ≥1 R/M HNSCC were treated with HB-200 intravenously (every 3 weeks [Q3W] then Q6W) in combination with pembrolizumab (200 mg Q3W or 400 mg Q6W). Safety, T cell response, and preliminary antitumor activity were assessed. Results: As of 12 January 2024, 42 patients with HPV16+ PD-L1+ R/M HNSCC (41 of oropharynx as primary cancer site) were treated with HB-200 plus pembrolizumab in the 1L setting. Median follow-up time was 5.6 months. Characteristics of this cohort included: median age 66 years (range 50-77), 41 (98%) male, 37 (88%) White, 14 (33%) with ≥ 10 pack/year smoking history, 40 (95%) check point inhibitor (CPI) naïve (2 received CPI in the adjuvant setting), and 21 (50%) with PD-L1 CPS ≥ 20. HB-200 + pembrolizumab were generally well tolerated. Grade ≥3 treatment-related adverse events (TRAEs) were reported in 6 (14%) patients, serious TRAEs in 3 (7%) patients, and TRAEs leading to treatment discontinuation in 2 (5%) patients. No treatment-related death were reported. Among 35 evaluable patients (those with ≥ 1 tumor response assessments), the overall response rate (ORR) was 43% (3 complete response [CR], 9 partial response [PR], 3 unconfirmed PR) and the disease control rate (DCR) was 71%. Notably, among patients with PD-L1 CPS ≥20 (N = 17), ORR was 59% (3 CR, 6 PR, 1 unconfirmed PR) and DCR was 88%. Conclusions: Updated data of HB-200 arenavirus-based immunotherapy plus pembrolizumab continued to demonstrate a favorable safety profile and promising clinical activity as 1L treatment in patients with HPV16+ PD-L1+ R/M HNSCC and confirms previously reported data. The results suggest that the subgroup of patients with PD-L1 CPS ≥20 may benefit more from this treatment, which warrants further development in a randomized pivotal study. Clinical trial# NCT04180215. Clinical trial information: NCT04180215 .

Striking the Balance with a PD-L1×4-1BB Bispecific Antibody.

Antibody-based immune checkpoint blockade therapy has revolutionized the field of cancer immunotherapy, yet its efficacy remains limited in immunologically cold tumors. Combining checkpoint inhibitors with costimulatory agonists improves tumoricidal activity of T cells but also can lead to off-target hepatotoxicity. Although bispecific antibodies confer tumor selectivity to alleviate undesirable adverse effects, toxicity concerns persist with increased dosing. In this issue of Cancer Research, Yuwen and colleagues introduce ATG-101, a tetravalent PD-L1×4-1BB bispecific antibody with high programmed death ligand 1 (PD-L1) affinity and low 4-1BB affinity, aiming to mitigate hepatotoxicity. ATG-101 demonstrates PD-L1-dependent 4-1BB activation, leading to selective T-cell activation within the tumor microenvironment. ATG-101 exhibits potent antitumor activity, even in large, immunologically cold, and monotherapy-resistant tumor models. Single-cell RNA sequencing reveals significant shifts of immune cell populations in the tumor microenvironment from protumor to antitumor phenotypes following ATG-101 treatment. In cynomolgus monkeys, no serious cytokine storm and hepatotoxicity are observed after ATG-101 treatment, indicating a broad therapeutic window for ATG-101 in cancer treatment. This study highlights the potential of tetravalent bispecific antibodies in cancer immunotherapy, with implications for various antibody-based treatment modalities across different fields. See related article by Yuwen et al., p. 1680.

Transmural Flow Upregulates PD-L1 Expression in Microvascular Networks.

Endothelial programmed death-ligand 1 (PD-L1) expression is higher in tumors than in normal tissues. Also, tumoral vasculatures tend to be leakier than normal vessels leading to a higher trans-endothelial or transmural fluid flow. However, it is not clear whether such elevated transmural flow can control endothelial PD-L1 expression. Here, a new microfluidic device is developed to investigate the relationship between transmural flow and PD-L1 expression in microvascular networks (MVNs). After treating the MVNs with transmural flow for 24h, the expression of PD-L1 in endothelial cells is upregulated. Additionally, CD8 T cell activation by phytohemagglutinin (PHA) is suppressed when cultured in the MVNs pre-conditioned with transmural flow. Moreover, transmural flow is able to further increase PD-L1 expression in the vessels formed in the tumor microenvironment. Finally, by utilizing blocking antibodies and knock-out assays, it is found that transmural flow-driven PD-L1 upregulation is controlled by integrin αVβ3. Overall, this study provides a new biophysical explanation for high PD-L1 expression in tumoral vasculatures.

Three-Year Overall Survival Outcomes and Correlative Analyses in Patients With NSCLC and High (50%–89%) Versus Very High (≥90%) Programmed Death-Ligand 1 Expression Treated With First-Line Pembrolizumab or Cemiplimab

IntroductionResponses to first-line programmed cell death protein 1 inhibition vary among patients with metastatic NSCLC and a programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) greater than or equal to 50%. We previously reported improved clinical outcomes to first-line programmed cell death protein 1 inhibition in patients with metastatic NSCLC with a PD-L1 TPS of greater than or equal to 90% versus 50% to 89% in a pilot study. Here, we report the three-year survival with first-line pembrolizumab and cemiplimab in two large independent cohorts of patients with PD-L1 TPS greater than or equal to 90% versus 50% to 89% and characterize genomic and immunophenotypic differences between these PD-L1 expression groups, which were largely unknown. MethodsWe analyzed three-year outcomes of the following two independent cohorts: (1) a multicenter cohort of patients from four academic centers in the United States treated with pembrolizumab and (2) EMPOWER-Lung 1, randomized, phase III trial comparing first-line cemiplimab with chemotherapy. Tumor genomic profiling and multiplexed immunofluorescence were performed to evaluate genomic and immunophenotypic correlates of very high PD-L1 expression. ResultsAt three years of follow-up, progression-free survival (hazard ratio [HR], 0.69; p < 0.001) and overall survival (HR, 0.70; p < 0.01) to first-line commercial pembrolizumab were significantly improved in patients with a PD-L1 TPS greater than or equal to 90% versus 50% to 89%. In the EMPOWER-Lung 1, patients assigned to the cemiplimab arm with a PD-L1 TPS greater than or equal to 90% also had significant improvements in progression-free survival (HR, 0.53; p < 0.0001) and overall survival (HR, 0.63; p = 0.007) compared with those with a PD-L1 of 50% to 89%. Tumor genomic profiling of 553 NSCLC samples revealed that mutations in STK11 and SMARCA4 were significantly more frequent in tumors with a PD-L1 TPS of 50% to 89% compared with those with a PD-L1 TPS greater than or equal to 90% (Q < 0.15), whereas BRCA2 was enriched in NSCLC samples with a PD-L1 TPS greater than or equal to 90% (Q < 0.15). Multiplexed immunofluorescence on 93 NSCLC samples identified higher intratumoral CD8+PD1+ T cells (p = 0.02) in tumors with PD-L1 TPS greater than or equal to 90% versus 50% to 89%. ConclusionPembrolizumab and cemiplimab were found to have long-term survival benefit and favorable genomic and immunophenotypic profile in patients with advanced NSCLC with PD-L1 TPS greater than or equal to 90% compared with TPS 50% to 89%.

High PD-L1 expression on immune cells along with increased density of tumor-infiltrating lymphocytes predicts a favorable survival outcome for patients with loco-regionally advanced head and neck cancer: early results from a prospective study.

In the era of personalized medicine and treatment optimization, use of immune biomarkers holds promise for estimating the prognosis of patients with head and neck squamous cell carcinoma (HNSCC) undergoing definitive treatment. To evaluate the prognostic potential of immune biomarkers, we conducted a prospective monocentric cohort study with loco-regionally advanced HNSCC patients indicated for definitive radiotherapy/radiochemotherapy at the Department of Oncology, Ostrava University Hospital, Czech Republic, between June 2020 and August 2023. We focused on the expression of programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) relative to overall survival (OS) and specific survival rates. Associations between biomarkers and survival rates were assessed by crude and adjusted hazard ratios (cHR, aHR, respectively) obtained from Cox proportional hazards regression. Among a total of 55 patients within a median follow-up of 19.7 months, there were 21 (38.2%) all-cause deaths and 15 (27.3%) cancer-related deaths. An overall survival (OS) rate of 61.8% and a disease-specific survival (DSS) rate of 72.7% were recorded. A significant association between survival rates and a ≥10% difference in PD-L1 expression on immune versus tumor cells (high PD-L1IC expression) was documented regardless of the type of analysis (univariate or multivariate). In addition, a stronger association was confirmed for OS and the composite biomarker high PD-L1IC expression along with either median-higher CD8+ TIL count or increased TIL density ≥30%, as indicated by an aHR of 0.08 (95% CI, 0.01 to 0.52) and 0.07 (95% CI, 0.01 to 0.46), respectively. Similar results were demonstrated for other specific survival rates. The early outcomes of the present study suggest the utility of a strong prognostic factor involving a composite biomarker high PD-L1IC expression along with increased TIL density in HNSCC patients undergoing definitive radiotherapy and radiochemotherapy. The study is registered with Clinicaltrials.gov. - NCT05941676.

Abstract 6829: Identification of immune suppressive features in tumor-associated endothelial cells (TECs) in EGFR-mutant non-small cell lung cancer via single-cell RNA sequencing

Abstract Introduction: Within the tumor microenvironment (TME), tumor-associated endothelial cells (TECs) exhibit distinct features from normal cells, and diverse phenotypes of TECs result in intratumoral heterogeneity. Here, we aimed to characterize the phenotypes of the TECs of non-small cell lung cancer (NSCLC), identify distinct features that are pivotal in tumor progression, and discover potential therapeutic applications. Methods: We performed single-cell RNA sequencing (scRNA-seq) from 128 NSCLC patients to include I (N=52), II (N=18), III (N=21), and IV (N=14), and compared them with normal cells (N=24). Epidermal growth factor receptor (EGFR)-mutant accounted for 69 samples. EGFR-wild (N=35) was further classified as programmed death-ligand 1 (PD-L1) high (N=14) and low (N=21) with PD-L1 high defined as tumor proportion score &amp;gt; 50%. Results: Twelve distinct EC types were characterized based on clinical information, including EGFR mutations and PD-L1 expression. We classified our subset as normal cells and tumor-enriched ECs, which were further classified as EGFR-wild or mutant ECs. Compared to normal cells, phenotypes such as activated post-capillary veins (APCVs), tip ECs, and endothelial mesenchymal transition (endoMT) ECs were predominantly observed in all tumor-enriched ECs. In EGFR-mutant ECs, ribosomal ECs, and vascular mimicry (VM) ECs were primarily enriched. Trajectory analysis showed that endoMT and VM ECs had lineage tracing of fibroblasts and epithelial cells, respectively. By clinical stage, APCVs, tip ECs, endoMT, and VM ECs were more enriched at advanced stages. PD-L1-high subset had higher expression of adhesion molecules, APCVs, and median transmigration score than other phenotypes. Also, high endothelial venules (HEVs) mediating lymphocyte trafficking to lymphoid organs were enriched in high PD-L1 subset. In the APCVs of EGFR-mutant group, there were interactions related to immune cell suppression and interactions of chemokines/chemokine receptors involved in recruitment. Conclusion: Our findings reveal distinct phenotypes of ECs, including the enrichment of APCVs, tip ECs, and endoMT ECs in all tumor-enriched EC populations, as well as VM ECs in EGFR-mutant ECs. APCVs, which is abundant high PD-L1 subset, play a crucial role in the transmigration progress of immune cells across vascular endothelium. In EGFR-mutant NSCLC, dysfunctional immune cells are recruited into the tumor, along with relatively low transmigration, resulting in poor tumor-killing effect. Citation Format: Su-Jin Choi, Jii Bum Lee, Kyoung-Ho Pyo, Gang-Taik Lee, YoungJoon Park, You Won Lee, Mi Ran Yun, Kyumin Lim, JuHyeon Lee, Min Hee Hong, Sun Min Lim, Byoung Chul Cho. Identification of immune suppressive features in tumor-associated endothelial cells (TECs) in EGFR-mutant non-small cell lung cancer via single-cell RNA sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6829.

Efficacy Assessment of Post-nephrectomy Adjuvant Therapies in Patients with Renal Cell Carcinoma.

The objective of our study was to integrate the efficacy results of post-nephrectomy adjuvant therapies in renal cell carcinoma (RCC) patients with risk of recurrence, and attempt to determine the optimal intervention choice. We performed standard meta-analysis procedures in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed, Embase, and Cochrane Library databases were searched from inception to 22 September 2022. Randomized controlled trials reporting overall survival (OS) or disease-free survival (DFS) of adjuvant therapies, including immune checkpoint inhibitors (ICIs) and targeted therapies, in adult post-nephrectomy RCC patients were eligible for inclusion. Seven studies involving 7548 participants were included in our analyses. In contrast with placebo, DFS benefit with ICIs was only observed in female RCC patients and RCC patients with high programmed death-ligand 1 (PD-L1) expression (≥ 1%), sarcomatoid features, and M0 intermediate-high risk. Network meta-analyses demonstrated that pembrolizumab exhibited both DFS and OS benefit compared with placebo, sunitinib, sorafenib, and girentuximab, and only DFS benefit compared with atezolizumab and nivolumab plus ipilimumab. Our results suggest that post-nephrectomy RCC patients with sarcomatoid differentiation and high PD-L1 expression were more responsive to ICIs. Furthermore, pembrolizumab monotherapy exhibited superior DFS and OS results over other adjuvant therapies.